Pneumatic-despatch-tube apparatus.



G. P. STODDARD. PNEUMATIG DESPATGH TUBE APPARATUS.

APPLIGATION FILED mm 25. 190B.

Patented Dec. 28, 1909.

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UNITED STATES PATENT CFFTQE.

CHARLES F. STODDARD, OF BOSTON, MASSACHUSETTS,

ASSIGNOR, BY MESNE ASSIGN- MENTS, TO AMERICAN PNEUMATIC SERVICE COMPANY, OF DOVER, DELAWARE. A

CORPORATION OF DELAWARE.

Specification of Letters Patent.

Patented Dec. 28, 1909.

Application filed July 25, 1808. Serial No. 445,290.

To all whom it may concern:

Be it known that 1, CHARLES F. S'roonann, of Dorohester, Boston, in the county of Suffolk and State of Massachusetts, have invented certain new and useful Improvements in Pneuinatic-Despatch-Tube Apparatus, of which the following is a specification.

My invention relates to im )rovements in pneumatic despatch apparatus and especially to a sending terminal by means of which carriers are inserted into the tube.

In sending terminals such as described in my Patent No. 742,513 issued Oct. 27, 1908 the gates or valves which act as a lock and keeps the pressure in the tube from escaping when a carrier is inserted are constructed to open by the weight of a carrier and are counter-balanced in such a way as to close by themselves after a carrier has passed from under them. In closing these valves attain considerable momentum and are liable to banging against their seats. This banging is the cause of noise and also wear on the face of the valve and its seat.

The principal object of my invention is a means of stopping this banging and I accomplish it by transferring, as it were, the momentum or the valve just before it reaches its seat to a secondary moving member. Thereby arresting the motion of the valve just before it reaches its seat and causing it to close gently;

In the accompanying drawings which illustrate a construction embodying my invention, Figure 1 is a longitudinal section of a complete transmitting terminal showing the inertia stops in two difierent positions. Fig. 2 is a longitudinal section of the lower valve and easing showing the valve in a third and intermediate position.

Like letters of reference refer to like parts throughout the several views.

The operation of the transmitting terminal of the type here shown is fully described in Patent No. 742,513 and as my present invention is applicable to any type of transmitter equipped with self-closing valves I will only explain the action of the valves and inertia stops.

The inertia stops A A swing very freely on the shafts B B, their motion being limited by the lugs C C, engaging either the shoulders C C or C C. The centers of gravity of the inertia stops A A are very slightly to the rear of their centers, so that the slight excess of weight on this side tends to keep them in the position shown in Fig. 2 with the lug C resting against the shoulder C Part of the forward sides of the inertia stops A A are cut away as shown at A A in such a way as to form respectively the shoulders A A which are engaged by the counter-balance arms D D. The shafts E E are secured in the valve casings F F and upon them swing freely the coimter-balanced arms D D to which are fastened the valves Gr G by means of the pins H H. The valves G G close against their seats J J. The valves and counter-balanced arms are constructed so that their centers of gravity are slightly to the rear of the shafts E E so that they tend to assume the position of valve Gr, Fig. 1. The overbalancing of the valves G G and the counter-balanced arms D D is slightly greater than that of the inertia stops A A so that when the moving members come to rest they will be in the position of the set shown in Fig. 1 in which the valve G is closed.

The operation is as follows: Normally the parts are in the positions shown in Fig. 1, valve G with the lug C raised slightly off the shoulder C WVhen a carrier opens a valve to pass under it, the parts assume the positions shown in Fig. 1, valve G the inertia stop A swinging around so that the lug G rests on the shoulder C After the carrier passes from under the valve the valve starts to swing closed but when it reaches the position shown in Fig. 2 the counterbalanced. arm D engages the shoulder A of the inertia stop A imparting to the inertia stop A its momentum and thereby swinging the inertia stop A around on the shaft B so that the lug C moves in the direction of the shoulder C and if enough motion is imparted to the inertia stop A the lug C will engage the shoulder C and its motion will be stopped and it will swing back toward its first position. After the shoulder A is struck by the counter-balance arm D, and moved away, the valve G closes gently by its own weight. The inertia stop then swings back and in the case of the lower valve bounces once 'keeps the valve from moving open when struck by the rebound of the inertia stop and there is no bouncing.

Having thus described the nature of my invention and set forth a construction embodying the same, what I claim as new and I desire to secure by Letters Patent of the United States is:

1. In pneumatic despatch tube apparatus, a transmission tube, a sender communicating with said transmission tube, a valve op erating to close said sender to the atmosphere, and an inertia stop mounted to oscillate independently of said valve and operating to engage said valve to check the movement of the same.

2. In pneumatic despatch tube apparatus, a transmission tube, a sender communicating with said transmission tube, a valve operating to close said sender to the atmosphere, an inertia stop mounted to oscillate independently of said valve and operating to engage said valve to check the movement I of the same, and means for limiting the 0scillations of said inertia stop.

3. In pneumatic despatch tubeapparatus, a transmlsslon tube, a sender communieat ing with said transmission tube, a valve operating to close said sender to the atmosphere and an ecc'entrically weighted inertia stop mounted to oscillate independently of said valve and operating to engagesaid valve to check the movement of the same.

4. In pneumatic despatch tube apparatus, a transmlssion tube, asender communicating with said transmission tube, a valveopcrating to close said sender to the atmoss phere, an eceentrically weighted lnertia stop mounted to oscillate independently of said J valve and operating to engage said valve to check the movement of the same, and means for hunting the osclllatlons of said inertia stop.

In testimony whereof, I have signed any name to this specification in the presence of two subscribing witnesses, this seventeenth day of July A. D. 1908.

CHARLES F. STODDARD.

' I/Vitnesses: a

A. PARLETT LLOYD, C. R. Bowln. 

